The following steps outline how to determine the appropriate coordinate space for a SAS Visual Analytics polygon provider or geography data item when using data originating from an Esri ArcGIS shapefile.These steps use information from an Esri .prj file and SpatialReference.org.

1. Identify the projection for the Esri ArcGIS polygon data
   
   Projection information is contained in the .prj file that is associated with an Esri .shp file. Open the .prj file in a text editor.
   
   Here is an example of a .prj file:
   
   

   PROJCS["NAD_1983_10TM_AEP_Resource",

   GEOGCS["GCS_North_American_1983",

   DATUM["D_North_American_1983",

   SPHEROID["GRS_1980",6378137.0,298.257222101]],

   PRIMEM["Greenwich",0.0],

   UNIT["Degree",0.0174532925199433]],

   PROJECTION["Transverse_Mercator"],

   PARAMETER["False_Easting",0.0],

   PARAMETER["False_Northing",0.0],

   PARAMETER["Central_Meridian",-115.0],

   PARAMETER["Scale_Factor",0.9992],

   PARAMETER["Latitude_Of_Origin",0.0],

   UNIT["Meter",1.0]]

   
   
   
2.  Search for the projection in the PROJCS value on www.SpatialReference.org
   
   For example, in the .prj file from item 1, PROJCS=NAD_1983_10TM_AEP_Resource. This value leads us to https://spatialreference.org/ref/esri/102185/.
   
   The following display shows SpatialReference.org for projection 6871.
   
   
   
3. Confirm that projection details match between the .prj file and the specific projection site on https://spatialreference.org/ref/esri/102185/.
   
   As shown in the following display, click the link for Well Known Text as HTML in order to verify projection details.
   
   
   Verify the projection parameters on this page with the parameters in the Esri .prj file.
   
   
   
4. If the details match, click the Proj4 link for the projection in order to get the coordinate space information.
   
   
   Information listed on the Proj4 page is the coordinate space value for the SAS Visual Analytics polygon provider or geography data item.
   
   Note: If the Proj4 page is blank (no text), then the Esri polygon data must be re-projected to EPSG:4326 using the SAS procedure PROC GPROJECT.
   
   
   
5. Use the SpatialReference.org PROJ4 information as the coordinate space value in the SAS Visual Analytics polygon provider or geography data item.
   
   Continuing with the same example, use the following string as the coordinate space in SAS Visual Analytics.
   
   +proj=tmerc +lat_0=0 +lon_0=-115 +k=0.9992 +x_0=0 +y_0=0 +ellps=GRS80 +units=m +no_defs
   
   The following displays illustrate this step: